In a dense network, a large number of small cells are deployed in a planned or unplanned manner to meet the traffic demands of the existing mobile services. The small cells are deployed in addition to the umbrella macro cell that is primarily designed to provide coverage. The small cells are intended to provide data intensive services which cannot be provided to a satisfactory level by the existing networks. The existing networks already employ the deployment of small cells in hotspots to cater to the localized data surge. As per the 3rd generation partnership project (3GPP) long term evolution (LTE) networks, a number of small cells (e.g., ranging from 1 to 10) can be deployed per macro cell. However, multiple studies have concluded that the deployment of small cells per macro cell is not enough to meet the projected data needs of the future data intensive mobile services. Hence, a study is underway to increase the number of small cells that can be deployed under a macro cell in 3GPP release 12.
When a large number (e.g., >10) of small cells are deployed under a macrocell, simulations have shown that the small cells cause a large amount of interference among themselves, due to which the effective user data throughput does not scale in proportion to the number of small cells deployed. The reason that the effective user data throughput does not scale up is that a number of small cells are typically deployed in a cluster to serve a hotspot in the unplanned manner. Accordingly, a lot of effort is required to deploy the small cells in the planned manner. However, despite the effort for deploying the small cells in the planned manner, the effective user data throughput has not thus far increased enough.
The current research bodies are attempting to devise smarter interference mitigation schemes to address the interference problem among small cells. However, the interference mitigation schemes to address the interference problem cannot be used at a subframe level. It is because in a case where the small cells are connected to each other and the overlaid (umbrella) macro cell via the non-ideal backhaul, the delay is in the order of tens of milliseconds while the subframe in 3GPP LTE is 1 ms.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present disclosure.